Sensing devices for cigarette packing machines



Dec.- 26 1967 SCHMERM-UND 313601558 SENSING DEVICES FOR CIGARETTE PACKING MACHINES Filed June 4, 1963 5 Sheets-Sheet 1 Fig.1

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1 INVENTOR:

ALFRED SCHMERMUND BY -Jfda FM ATTORNEYJ Dec. 26, 1967 v SCHMERMUND 3,360,658

SENSING DEVICES FOR CIGARETTE PACKING MACHINES I Filed June 4, 196 5 I 5 Sheets-Sheet 2 m i a m? INVENro);

A LFR ED SCHMERMUND BY draft; fir/Mte A TTORNEYJ' Dec. 26, 19 67 3,360,658

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'ij i0 14 j0 JZ gfifa )N VENTOR ALFRED SCHMERMUND BY 175512 @flzl Y. r ron'lvawnr United States Patent 3,360,658 SENSING DEVICES FOR CIGARETTE PACKING MACHINES Alfred Schmermund, 62 Karnerstrasse, Gevelsberg, Westphalia, Germany Filed June 4, 1963, Ser. No. 285,312 Claims priority, application Germany, June 8, 1962, Sch 31,597 8 Claims. (Cl. 250-231) The invention relates to devices for sensing the presence or absence of articles and more especially relates to devices for sensing the presence or absence of cigarettes in a block of cigarettes in a cigarette packing machine.

In cigarette packing machines, cigarettes are fed in blocks, that is to say groups of cigarettes lying side by side and in several layers one above the other. For instance, a block of twenty cigarettes may comprise three layers, of which one layer has six cigarettes and is disposed bctween two layers each of seven cigarettes.

To prevent the packing of blocks of cigarettes which are incomplete or of which a cigarette is imperfect, for instance incompletely filled or lacking a filter tip, sensing devices are used in packing machines, for sensing the presence or absence of cigarettes at predetermined locations in the end area of the block, or for sensing an imperfection of a cigarette if present at one of said predetermined locations.

In a previously proposed sensing device, a sensing head has plungers spaced in an array corresponding to the array of the cigarettes in the block to be tested. Each plunger has a slot for the passage of a light beam therethrough and the slot is moved into the path of a light beam when the plunger is pressed back as a result of encountering a cigarette. The light beam is provided by an electric bulb, and prisms or mirrors are provided which change the path of the light beam so that the light beam passes from the light source successively through the slots of the plungers disposed at the various different levels in the array. After having passed through the slot of the last plunger, the light beam impinges on a light sensitive cell. If, as a result of failure of one or more plungers to be pushed back by a cigarette, the light beam is interrupted, then a control signal can be derived from the absence of illumination of the light sensitive cell.

It has been found that directing a light beam through plunger slots disposed in an array having two or three levels is cumbersome, since the light path becomes long and the amount of light available for impingement on the light sensitive cell is thus weakened.

It is an object of the invention to provide a device for sensing the presence or absence of articles arranged in a multi-layer array in which the light path is shortened as compared with previously suggested similar devices.

It is another object of the invention to provide a device for sensing the presence or absence of articles arranged in a multi-layer array, in which only a single transit of a light beam is required.

This and other objects and advantages of the invention will become clear from the following description when read in conjunction with the accompanying drawings, which are given by way of example and in which:

FIG. 1 is an end view of a cigarette block composed of twenty cigarettes;

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FIG. 2 is a sectional view, partly broken away, taken along the line E-F-G-H of FIG. 3, of a sensing device of the invention;

FIG. 3 is a cross-sectional view of the sensing device, taken along the line A-B of FIG. 2;

FIG. 4 is a sectional view, partly broken away, taken along the line 'II-KL of FIG. 5, of a modified embodiment of a sensing device;

FIG. 5 is a cross-sectional view of the sensing device of FIG. 4, taken along the line CD thereof;

FIG. 6 is a sectional view, partly broken away, taken along the line A-B of FIG. 7, of another sensing device of the invention;

FIG. 7 is a cross-sectional view of the sensing device of FIG. 6, taken along the line CD of FIG. 6;

FIG. 8 is a sectional view, partly broken away, taken along the line E-F of FIG. 9 of yet another sensing device of the invention; and

FIG. 9 is a cross-sectional view of the sensing device of FIG. 8, taken along the line G-H of FIG. 8.

The block of cigarettes 25 shown in FIG. 1 has three layers of cigarettes, the cigarettes lying closely against each other in such manner that the upper and lower layers each have seven cigarettes and the central layer has six cigarettes. Cigarettes are conventionally fed in cigarette packing machines in blocks of such make-up, for packing into packs of twenty cigarettes.

The sensing device of FIGS. 2 and 3 comprises a housing 1 in which twenty plungers 17 are slidably mounted, the plungers being guided in bores 22 of the housing 1 and in bearing sleeves 23 secured to the housing 1. Each plunger 17 has an end cap 24 which extends over the respective sleeve 23 and forms a seal preventing the entry of tobacco or dust into the housing 1 through the sleeves 23.

The plungers 17 are so disposed that the caps 24 form an array having three layers, just as do the cigarettes of the cigarette block to be tested, the longitudinal axes of the plungers having the same spacing as the longitudinal axes of the cigarettes.

Inside the housing 1, masking plates 18 are provided which are secured to the plungers 17,- one to each, the masking plates being secured by being folded around the respective plungers and riveted by rivets 26. Springs 21 acting between one inner wall of the housing 1 and the masking plates, urge the plungers 17 into the position shown in FIG. 3, in which the masking plates 18 abut on another inner wall of the housing 1.

The masking plates 18 of the plungers of the various layers are of different lengths, such that each masking plate extends to the same extent into a respective one of a plurality of channels 20 arranged in a comb-like manner in an upper part 2 of the housing 1.

The upper housing part 2 has a channel 19 which intersects each of the channels 20 at right angles. The masking plates 18 are so disposed on the plungers 17 that when the masking plates have the position shown in FIG. 3, the portions thereof which extend into the channels 20 close-off the channel 19.

The channel 19 at one of its ends opens onto a housing part 8 in which an electric lamp 11 is mounted by means of a socket 12, 13. A slotted diaphragm 42 is disposed between the lamp 11 and the channel 19. Contacts of, the socket 12, 13 are connected to a cable 10 which serves for supplying electric energy for the lamp 11. At its other end, the channel 19 opens onto a housing part 7 in which a light sensitive cell 14, such as a photo-resistor, is provided, the cell 14 being secured in a mount 15, 16 and connected to an electric cable 9.

The side of the housing 1 remote from the plunger caps 24 is closed by a cover 3, and the upper housing part 2 has a holding member 4 secured thereto, which is linked to levers of a parallelogram lever system, by pivots 6.

The sensing device of FIGS. 4 and 5 comprises a housing formed by two plates 28 and 31 which are held spaced apart by plates 29 and 30. This housing is secured to a cover member 27 by screws, the cover member being connected to a holding member 4 in the same Way as the housing part 2 of FIGS. 2. and 3. A front cover 35 is secured to the plate 28, the cover 35 and the plate 28 having bores through which nylon plungers 34 extend so as to be longitudinally slidable.

The ends of the plungers 34 which extend into the housing, are slotted, the slots seating masking plates 36 on the plungers 34 by friction and which are slidably guided in channels 32 disposed in a comb-like manner in the plate 29. Compression springs 33 engage the masking plates 36 and urge the masking plates 36 and therewith the plungers 34 into the position shown in FIG. 5. The compression springs 33 are seated on pins 41 set in blind bores in the plate 31.

Each of the channels 32 isintersected at right angles by a common channel 19 which at one end opens via a slotted diaphragm 42 onto a housing part 39 containing an electric lamp 11, a socket 12, 13 of which is connected to a cable 10. At its other end, the channel 19 opens onto a housing part 40 in which a light sensitive cell 14, such as a photo-resistor, is provided, the cell 14 being secured in a mount 15, 16 and connected to an electric cable 9.

The hollow space between the front cover 35 and the plate 28 is connected to a pressure-air line (not shown) so that the excess pressure in the said space prevents the entry of tobacco or dust through the bores in which the plungers 34 slide.

In operation of the devices so far described, two of the sensing devices are used, one for each end of the cigarette block to be tested. The sensing devices are moved into a feed path for the cigarette blocks and by means of the parallelogram lever systems 5 are moved so that the plungers engage the cigarettes and are pressed-in thereby.

If one or more cigarettes of the cigarette block is missing, or is not sufiiciently filled with tobacco at its end, or lacks a filter tip, for example, then one or more of the plungers is or are not pressed-in and consequently the light beam between the lamp 11 and the light sensitive cell 14 remains interrupted. By known electrical means (not shown) an impulse is thus derived which can be used for stopping the packing machine or for controlling rejection of the cigarette block being tested, or can be stored by a known impulse storing arrangement (not shown) for controlling ejection of the cigarette block at a predetermined later stage in the feed path of the cigarette blocks.

If all of the cigarettes in the cigarette block are present, and if none of the cigarettes have the above mentioned imperfections, then all of the plungers are pressed-in and all of the masking plates 'free the channel 19, allowing the lightbeam from the lamp 11 to reach the light sensitive cell 14.

Instead of the masking plates having the generally L- shaped form, which they have in the embodiments of FIGS. 2 to 5, and serving for masking the light beam unless moved from their initial positions, the masking plates may have slots formed therein for the passage of the light beam when all of the slots are aligned.

When it is desired that the sensitivity of response of the sensing device be adjustable, then, instead of the channels 20 being formed in a fixed housing part as shown in FIGS. 2 and 3, they may be formed in a slide 45 as shown in FIGS. 6 and 7. In this case the slide 45 is movable in a dovetailed slideway 44 by means of an adjusting screw 47 which engages a nut member 46 secured to the slide 45. Displacement of the slide 45 causes movement of the channel 19 relative to the masking plates 18 and thus varies the response sensitivity by varying the distance through which the plungers have to move before the masking plates 18 clear the channel 19.

Another possibility of adjusting the sensitivity is shown in FIGS. 8 and 9, this representing a modified form of the device of FIGS. 4 and 5. In this case, the masking plates 36 are displaceable relative to the plate 29. For this purpose, the plungers 34 extend through an abutment plate 51 which is connected by hubs 53 to two threaded studs 50 which are engaged from the outer side of the plate 31 by two nut members 49. The threaded studs 59 have guide studs 52 extending beyond the abutment plate 51 into bores in the plate 28, for slidably supporting the threaded studs 50. It will be appreciated that rotation of the nut members 49 enables the initial position of the masking plates 36 relative to the channel 19 to be adjusted.

It should be clearly understood that the embodiments described herein are given by way of example only. Modifications, omissions and additions are possible without departing from the spirit of the invention.

I claim:

1. In a sensing device for cigarette packing machines to sense cigarettes arranged in a plurality of layers, of the kind comprising a plurality of sensing plungers, means mounting said plungers slidably in the axial direction, said plungers being arranged in a plurality of parallel rows, a plurality of spring means urging said plungers into a first predetermined position, first means for holding a light source, second means for holding a light sensitive cell, a housing enclosing said first holding means and said second holding means and at least parts of said plungers, said plungers protruding from said housing when in said first position, the combination comprising means defining a single straight light channel in said housing between said first holding means and said second holding means for enabling a light beam to travel from said light source to said light sensitive cell, said light channel being parallel to said rows of plungers, and a plurality of masking members carried by said plungers, each plunger carrying one of said masking members, said masking members each extending perpendicular to said plungers and each being shaped and arranged to extend into said light channel to each block the same when said plungers are in said first position and to clear said light channel when said plungers are in a second predetermined position.

2. A sensing device as defined in claim 1, wherein said housing has a part formed with guide channels slidably receiving end portions of said masking members, said guide channels extending at right angles to said light channel.

3. A sensing device as defined in claim 2, wherein said housing part is rigid with said housing.

4. A sensing device as defined in claim 2, wherein said housing part i displaceably mounted relative to said housing in the direction of said guide channels.

5. A sensing device as defined in claim 2, and further comprising means for adjusting said initial position by displacing said masking members relative to said housing part.

6. A sensing device as defined in claim 1, wherein said masking members are riveted to said plungers.

7. A sensing device as defined in claim 1, wherein said masking members engage said plungers frictionally.

8. A sensing device as defined in claim 2, and comprising an abutment member, said plungers extending through said abutment member, and means for displacing said abutment member relative to said housing.

(References on following page) References Cited UNITED STATES PATENTS Arett et a1. 131-21 Page 250229 X Metcalf 250 231 5 Bush 250229 X Kflburn et a1. 250237 X Schrnermund 250222 6 FOREIGN PATENTS 775,226 5/1957 Great Britain.

WALTER STOLWEIN, Primary Examiner. RALPH G. NILSON, Examiner.

M. A. LEAVITT, E. STRICKLAND,

Assistant Examiners. 

1. IN A SENSING DEVICE FOR CIGARETTE PACKING MACHINES TO SENSE CIGARETTES ARRANGED IN A PLURALITY OF LAYERS, OF THE KIND COMPRISING A PLURALITY OF SENSING PLUNGERS, MEANS MOUNTING SAID PLUNGERS SLIDABLY IN THE AXIAL DIRECTION, SAID PLUNGERS BEING ARRANGED IN A PLURALITY OF PARALLEL ROWS, A PLURALITY OF SPRING MEANS URGING SAID PLUNGERS INTO A FIRST PREDETERMINED POSITION, FIRST MEANS FOR HOLDING A LIGHT SOURCE, SECOND MEANS FOR HOLDING A LIGHT SENSITIVE CELL, A HOUSING ENCLOSING SAID FIRST HOLDING MEANS AND SAID SECOND HOLDING MEANS AND AT LEAST PARTS OF SAID PLUNGERS, SAID PLUNGERS PROTRUDING FROM SAID HOUSING WHEN IN SAID FIRST POSITION, THE COMBINATION COMPRISING MEANS DEFINING A SINGLE STRAIGHT LIGHT CHANNEL IN SAID HOUSING BETWEEN SAID FIRST HOLDING MEANS AND SAID SECOND HOLDING MEANS FOR ENABLING A LIGHT BEAM TO TRAVEL FROM SAID LIGHT SOURCE TO SAID LIGHT SENSITIVE CELL, SAID LIGHT CHANNEL BEING PARALLEL TO SAID ROWS OF PLUNGERS, AND A PLURALITY OF MASKING MEMBERS CARRIED BY SAID PLUNGERS, EACH PLUNGER CARRYING ONE OF SAID MASKING MEMBERS, SAID MASKING MEMBERS EACH EXTENDING PERPENDICULAR TO SAID PLUNGERS AND EACH BEING SHAPED AND ARRANGED TO EXTEND INTO SAID LIGHT CHANNEL TO EACH BLOCK THE SAME WHEN SAID PLUNGERS ARE IN SAID FIRST POSITION AND TO CLEAR SAID LIGHT CHANNEL WHEN SAID PLUNGERS ARE IN A SECOND PREDETERMINED POSITION. 